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本文研究了我国南方三种酸性土壤（红壤、赤红壤和砖红壤）在去除铝键结合腐殖质和铁键结合腐殖质前后土壤微团聚体组成及腐殖质氧化稳定性的变化。结果表明：在以０．５ｍｏｌ·Ｌ－１ＮＨ４Ｆ（ｐＨ８．２）除去部分铝键结合腐殖质后，三种土壤的微团聚体组成中以５～１０μｍ粒级的变化最大，其中在红壤中该级数量急剧减少，小于５μｍ微团聚体增加；再以０．１ｍｏｌ·Ｌ－１Ｎａ４Ｐ２Ｏ７＋０．１ｍｏｌ·Ｌ－１ＮａＯＨ（ｐＨ１３）混合液处理后，赤红壤和砖红壤中５０～２５０μｍ微团聚体数量大幅降低，５～１０μｍ微团聚体则增加。在以ＮＨ４Ｆ除去部分铝键结合腐殖质后，残留于土壤中的腐殖质的氧化稳定性均略有增加，但幅度较小；继续以０．１ｍｏｌ·Ｌ－１Ｎａ４Ｐ２Ｏ７＋０．１ｍｏｌ·Ｌ－１ＮａＯＨ（ｐＨ１３）混合液进一步除去铁铝键复合体后，氧化稳定性则基本保持不变；三种土壤中各结合形态腐殖质的氧化稳定性均为红壤＞赤红壤＞砖红壤
In this paper, the composition of soil micro-aggregates and the oxidation stability of humus before and after removal of aluminum-bonded humus and iron-bonded humus were studied in three acidic soils in southern China (red, latosolic, and latosol). The results showed that after the removal of some aluminum-bonded humus with 0.5mol·L-1NH4F (pH8.2), the micro-aggregates of the three soils changed most significantly in the 5 ~ 10μm fractions. In the red soil, The amount of microaggregates decreased sharply and the microaggregates of less than 5μm increased. After treatment with 0.1mol·L-1Na4P2O7 + 0.1mol·L-1NaOH (pH13), the number of microaggregates of 50 ~ 250μm in red soil and brick red soil decreased significantly, 5 ~ 10μm microaggregates increased. After removing part of the aluminum-bonded humus with NH4F, the oxidation stability of humus remained in the soil slightly increased, but the magnitude was small; continue to mix with 0.1mol·L-1Na4P2O7 + 0.1mol·L-1NaOH (pH13) After the solution was further removed, the oxidation stability remained unchanged. The oxidation stability of the combined forms of humus in the three soils were red earth> red earth> brown soil